Hi,

We have the above identified outboard (1988 long shaft) on our 21'
trailer sailor. Bought 2 years ago from a from a fresh water sailor
(lake Ontario), and we sail on the Chesapeake (brackish). We flush
the motor after a sail about 50% of the time.

We replaced the impeller (disintegrated) last year, and the thermostat
this year. Did not note any obstructions in the observable coolant
passages.

The motor starts on the first pull, and seems to run fine. The
problem is that the cooling water indicator port (on the frame) only
streams water at ~1000rpm and above; below which it just steams.
During a stress test, we found the engine stalled after about 10
minutes of idling (& steaming).

Should the indicator port stream water at all rpms? Does the steam
indicate a cooling system problem?

Any guidance from someone with similar experience would be much
appreciated!

Thanks.